Dataset: Copepod escape direction
Deployment: CopepodEscape_2017

Copepods' approaches to and escapes from the source of a fluid disturbance were recorded on high-speed digital video (500 fps) in 3D. The optical set-up used is a scaled down version of a system described in Strickler (1998). The system, which uses beam splitters and prisms, generates in a single recorded image of two views, the front (x, z) and the side (y, z). These 3-D views were recorded high-speed digital video cameras (in Texas by a Photron FastCam Super 10K series, in Hawaii by a Kodak Motioncorder SR-3000) at 500 frames per second.

For the behavioral experiments, sets of individuals were transferred into the experimental chamber (1.25 x 1.25 x 4.5 cm) at densities of 7 to 15 ind mL-1 for nauplii, and 1.5 to 3 ind mL-1 for copepodites.  When one or more individuals were within the camera view the hydromechanical stimulus was triggered and a video sequence that included footage from before and after the trigger was recorded.

The hydromechanical stimulus:  a 3-mm diameter inert plastic sphere was attached to a stiff rod mounted to a piezoelectric pusher (DSM LPA 100 Dynamic Structures) and positioned in the upper quarter of the optical vessel.  A pulse trigger controlled the pusher, which displaced the sphere downward by 35 microns in 0.5 ms, returning it to its initial position 60 ms later.

Reference:
Strickler JR. 1998. Observing free-swimming copepods mating. Phil. Trans. R. Soc. Lond. B 353: 671-680.